Forest Floor Investigation
A L ABAM A O UT D O O R C L AS S ROO M A CT I VIT Y
Grade Levels
3-7
Overview
While exploring the forest floor,
the students will learn about the
various organisms that live in and
under the leaf litter, including a
variety of decomposers.
Subject Areas
Biology, Mathematics and
Environmental Sciences
Background Info
Leaves, sticks, logs and other organic materials are constantly being added to the
forest floor. With this constant flow of organic material being added to the forest
floor, it would be impossible within a short period of time to even walk around under
the forest canopy. Thanks to a host of small organisms (decomposers), this layer of
organic material is constantly being broken down (composted) into soil. If we look
closely at the forest floor, we will discover that there are a lot of organisms living
right under our feet. This activity will have the students examine the forest floor for
signs of life through a “hands-on” investigation. At the end of this activity, the
students will discover that there is an abundance of biodiversity inside an area the
size of a hula-hoop and that this biodiversity is vital to the health of a forest.
Preparation
Duration
Before doing this activity, find a place that has a tree canopy and room under the trees
to spread out several hula hoops. It will be even better if there is a nice layer of leaves
as well as rotting wood in the form of sticks, or logs scattered about. If an area of trees
Learning Objectives
is not available, then this activity may be done anywhere on the school-grounds or
1) Students will discover a variety of
organisms that live on the forest floor surrounding area. You will also want to make copies of the attached Nature Journal
while conducting an investigation.
Work Page.
1 period of 45 minutes
2) Students will identify and draw
sketches of organisms that they find
during this activity. 3) The students
will learn about the role that
decomposers play in the
environment.
Alabama Course of Study
Objectives (on page 2)
Vocabulary:
Fungi, fungi strands,
decomposers, organic, compost
Materials
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One hula-hoop per group of
students (4 students per group
works well)
One clipboard per student or
team of students
Copies of Worksheets (two
different worksheets attached)
One magnifying glass or
loupe per person
Trowels or other digging
tools
Clear containers for holding
moving organisms until
activity is finished
Page 1 of 2
Grade Level Variations
Grades K-2: This activity can be easily adapted for this age group. Have them focus
on the decomposition of leaves and how this helps enrich the soil by moving nutrients
from the leaves back into the soil where they are used by the tree again. Stress cycles
such as the life cycle and seasonal cycle with this age group.
Grades 3-5: This activity can be used as written with this age group. Stress cycles
such as the nutrient cycle, life cycle, and water cycle.
Grades 6-7: This activity can be used as written with this age group. Stress cycles
such as the nutrient cycle, life cycle, carbon-oxygen cycle, nitrogen cycle, and water
cycle.
Procedure
1. Introduce cycles to the class such as the
Life Cycle, Carbon-Oxygen Cycle, Nitrogen
Cycle, Water Cycle, Seasonal Cycle, etc. What
are some constant cycles that take place in the
forest environment? List these
cycles on a chart for further study if possible.
2. Today, we want to focus on the nutrient
cycle. Begin this discussion by asking the students what happens each fall to the trees
in a forest or their front yard? Why isn’t there a huge pile of leaves and other forest
material under the trees? What happens to all of this organic material? What kinds
of organisms do you think live in the forest that reduce this layer of organic material?
What happens to the nutrients that were used to produce this material?
3. Place the students into groups of approximately four students. Give each group a
hula-hoop, clipboard, and pencil. Give each student a magnifying glass to use for a
closer look at the living organisms they discover.
Forest Floor Investigation
A L ABAM A O UT D O O R C L AS S ROO M A CT I VIT Y
Alabama Course of Study
Objectives
Science:
Procedure continued...
4. Instruct the students that their job today is to help count the types and numbers of
organisms that live in an area the size of their hula-hoop.
Kindergarten: 6, 7, 8
First: 1, 4, 7, 10
5. Have the students place the hula-hoop on the forest floor. Once they have placed
Second: 5, 6, 7
the hoop and have started the activity, do not let them move the hoop to a new locaThird: 2, 7, 8,10, 13
tion as this is their survey area.
Fourth: 5, 6
6. (Observation #1) Begin the activity by having the students take the observation
Fifth: 9
worksheet and begin observing the area inside the hoop. They are to record all of the
Sixth: 3, 7
Seventh: 1, 4, 5, 7
organisms (living and not living anymore) that they see inside the hoop on the worksheet. While doing the first step of the activity, do not let them touch or move anyLiterature Connections:
thing inside the hoop. This step will take between 5 and 10 minutes. If they find any
Cooper, Sharon Katz, Rotten Logs
moving organisms, they may place then in the plastic collection containers.
and Forest Floors
7. (Observation #2) Once they have observed the surface, have the students carefully
ISBN-978-1-4109-3501-4
remove the leaves and sticks without digging in the soil and tell them to watch for
Pascoe, Elaine, Nature Close-Up
living things. Caution the students not to harm any of the living organisms and
Juniors: Forest Floor,
do not step inside the hoop. Have them lay the items around the outside of the cirISBN-10:1410303144
cle. When they see an organism, they need to record its presences on the worksheet.
Outdoor Classroom Connection If it is something they have already seen they will need to make a tally mark beside
Students will learn about the forest
the organism so that they can record a population total. They also need to list at least
floor and the various organisms that
three adjectives about each of the organisms they find. They also need to observe
can be found living there, including
how the structure of the leaves changes as they move from the top layer to the bottom
decomposers.
layer.
8. (Observation #3) Once the leaves have been removed, they may use the digging
Other Related Conservation
tools to carefully excavate the soil to a depth of about 4-6 inches. As they do the digEducation Activities
ging, have the students record any organisms that they see in the soil.
Project Learning Tree
9. Once all three observations are completed, have the students return the soil,
 The Forest of S.T. Shrew
organisms and leaves to the area.
 The Fallen Log
 Nature’s Recyclers
10. Have the students describe what they see and have them share their observations.
For example, they should have noticed that the leaves are being broken down as you
Access Nature
move from the top layer to the soil surface. They should also notice that the color of
 Compost Crazy
the soil may change as you dig downward into the soil. They will also notice that digging in the forest is very hard due to the roots that are located in the soil.
Project WILD
11. Have the students construct graphs to show what and how many organisms they
 Eco Enrichers
found in their area.
Extensions
1. Have the students repeat this activity in other areas that have a different use. For
example, repeat the activity in a grassy yard or on a bare ground playground.
2. Have each student write a descriptive paragraph about one of the organisms (they
Page 2 of 2
could do research about that organisms) that they discovered, using the adjectives that
they recorded earlier.
The Alabama Outdoor Classroom Program is a partnership between:
Alabama Cooperative
Extension System
Alabama Wildlife Federation
www.alabamawildlife.org/classrooms/
Alabama Department of
Conservation & Natural Resources
Date: ___________________________
Name of Naturalist: _________________________________
Forest Floor Investigation Activity Page
Please complete the sections marked with a millipede
first, before completing the rest of the page. Please include sketches of what you observe and use tally marks beside you drawings if you find more than one member of each specimen.
What do you think you will find on the surface (don’t disturb the area) of your sample area?
List what you observe in your sample area without disturbing the surface area.
What do you think you will find under the leaf litter in your sample area?
List what you observe while carefully removing the leaf litter, but don’t disturb the soil.
What do you think you will find in the soil once you start digging in your sample area?
List what you observe while digging below the surface.
Name: _______________________
Date: ____________
Getting Down and Dirty With Nature
Forest Floor Investigation
While examining the forest floor, complete a specimen data square for each specimen that
you discover during your investigation. There are more spaces on the back of the work page.
Description:
Description:
Drawing
Drawing:
Description:
Description:
Drawing:
Drawing:
Description:
Description:
Drawing:
Drawing:
Page 1 of 2
Description:
Description:
Drawing:
Drawing
Description:
Description:
Drawing:
Drawing:
Description:
Description:
Drawing:
Drawing:
Description:
Description:
Drawing:
Drawing:
The Alabama Outdoor Classroom Program is a partnership between:
Alabama Cooperative Extension System
Alabama Wildlife Federation
Page 2 of 2
Alabama Department of
Conservation & Natural Resources